RT Journal Article SR Electronic T1 Circumcision reduced the risk of contracting HIV infection in young sexually active Kenyan men JF Evidence Based Medicine JO Evid Based Med FD BMJ Publishing Group Ltd SP 104 OP 104 DO 10.1136/ebm.12.4.104 VO 12 IS 4 YR 2007 UL http://ebm.bmj.com/content/12/4/104.abstract AB